Answer: The correct answer is C. The President signed an executive agreement with the President of Peru.
Foreign policy refers to a government's strategies and actions towards other countries, including diplomatic, economic, and military relations. An executive agreement is a type of international agreement made by the President with a foreign government or international organization, without requiring Senate approval. Therefore, signing an executive agreement is an example of a foreign-policy decision.
The other options are examples of domestic policy decisions.
A. The President issued an Executive Order against cyber-bullying - This is an example of a domestic policy decision aimed at addressing a social problem within the United States.
B. Congress raised the residency requirement for naturalization to 7 years - This is also a domestic policy decision that affects the requirements for becoming a citizen of the United States.
D. The Supreme Court upheld the constitutionality of the Affordable Care Act - This is a judicial decision that addresses the constitutionality of a domestic policy issue, specifically the Affordable Care Act, a healthcare policy in the United States.